I agree with Art on this one. It's just the way things are. You have to sing a song in a way that fits your style and personality and point of view.
Frank, I love that quote about 'a photograph of a bird in flight'.

Jeri, I guess that IS putting one's own stamp on it, but it shouldn't be a deliberate thing. It just happens that way. I made some changes when I sang Kat's song "That's not my Colorado". It wasn't to say that I didn't like the way she wrote it, it sounds just right for her when she sings it. It just didn't 'feel' right to me when I was singing it. A song can sound awkward and stilted if the words don't fit you. You have to tweak words here and there to fit your own heritage.

Bert.